Different BB=Different OS?

Do different models of BB on differeing carriers have different OS? I am in the process of upgrading from a Curve 8330 to Tour and wanted to know how this works with the OS. If I got a Bold would the OS be different? Or another Curve would the OS be different?

For instance, the OS for the Curve is not only a different version than it is for the Tour, it is specifically ported for an 8330 Curve. The OS for the Tour is specifically for the Tour. Each carrier has its "official" OS version release, but you can install any OS from any carrier for that specific device (there are a few tricks to this, but it works).

As travelingfool said, each device will have different versions. The Bold 9700 comes
with some variation of OS 5.0, The Curve 8900 comes with a version of OS 4.6, the
Bold 9000 comes with 4.5, the Tour 9630 comes with 4.7 (I believe)

Within each of those variations there are different build versions. This you would be
able to tell by looking at the last three digits of the OS i.e OS 5.0.0.405 is OS 5.0,
build version .405

The build differences are typically not visible to the user. For instance, the 9700 has 256MB of flash, so its build allows for that where as other devices only have 128MB. The 9700 has the track pad so the code is a little different than that used in devices that have a trackball. All devices running 5.0.0.xxx should be the same to the user reguardless of the device (aside from bug fixes).

As for the providers' "offical" version, each provider will test and support a specific version of your BB's firmware. If a bug is know for build, your provider will know how to handle only those covered in a build they claim as "official". There is no reason that you can't run a newer version on your device, however your provider may not be able to answer ALL your questions if it relates to a change made in a newer build.

Ok. I am trying to understand it all! The 8330 was my first and only BB and I understand that the OS for the Tour has been buggy. I wondered if it was the same OS for all BB.

And to sort of focus on your particular devices, the Tour 9630 official OS release from Verizon is 5.0.0.591, and I've never had any issues with this release, however, Sprint released 5.0.0.484 for the Tour, and that version can be loaded on your Verizon Tour, with an added step or two to make it compatable.